getFunctionBody error

# Bug report

## Describe the bug

```
const body = await client.getFunctionBody(project, 'hello-world');
```
cause error:

<img width="1244" height="762" alt="Image" src="https://github.com/user-attachments/assets/775037fb-80c9-40c7-bdca-a6c84b5ad308" />

Seems body is not a json

